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2003 Audi Allroad HID headlight problem

My wife has a 2003 Audi Allroad (A6) with HID/xenon headlights. The passenger side low beam went out last night and the warning light came on in the car. When I turn the switch off and back on the headlight flashes on for a split second and then goes off. Could this be the bulb or the ignitor or both? I don’t have much experience with HID lights so I am starting fresh with this. Thanks.

I can’t believe no one has run into this problem. My next move is to switch bulbs and see if the problem is still there.

Its most likely the ballast (starter, ignitor, whatever you want to call it). The old guys here don’t like HID’s so they’d rather it be burned out on your car.

I thought I would add a reply. I have not dealt specifically with automotive arc lamps and circuitry but have dealt with arc lamps in other applications. Usually there is a high voltage ignition on start up to get the arc initiated then there is a sustain voltage to hold the arc. Usually when arc lamps fail, you will get the flickering start arc, even with a bad lamp.

The most likely candidate is a failed lamp. However, if the lamp connectors are available, the sustain voltage and amperage (with a good lamp running) should be checked.

Anyone who is willing to share their specific experience with diagnosing, lamp replacement, and power verification is welcome to enlighten us further.

To me it sounds like the ballast. From what I understand, an HID headlight system basically consists of the bulb, igniter and ballast. It sounds like your bulb and igniter are OK - the lamp lights up. The fact that it’s not staying lit would indicate to me that you have a bad ballast (the unit that sustains the high voltage to maintain the HID arc). I had this problem with my '00 Acura but now my headlight seems to stay on. Maybe if I left my headlights on for longer the light would go out. Anyway, HID headlight parts ain’t cheap. Good luck!